Malicious PDF — malware analysis report

Static analysis result for SHA-256 da3a33782a8ac3c9…

MALICIOUS

PDF

37.5 KB Created: 2020-09-01 01:46:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ecfd6937db773d57ef4ec76e21e71b47 SHA-1: 679d59dd95762a9129b3d4f359ab67b3cdab1985 SHA-256: da3a33782a8ac3c9a8d72786f7925d7ca07993728852c62beaf12bc67cb18b1e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded links, with one identified as a malicious redirector. The primary malicious URL, https://ttraff.ru/wix?keyword=free++water+brushes+for+photoshop+cs6, is used in a link farm strategy. This indicates an attempt to lure users to malicious content, likely for phishing or to download further malware. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/wix?keyword=free++water+brushes+for+photoshop+cs6
    • https://static.usrfiles.com/ugd/963627_4e02a6e5b9434d3e9d61fffff255a678.pdf
    • https://static.usrfiles.com/ugd/c7ef1a_c1158f17348a442a8f5a0f5611ea75b6.pdf
    • https://static.usrfiles.com/ugd/38bf1f_24853b44de1b47a5a72f61c808efba93.pdf
    • https://cdn.shopify.com/s/files/1/0429/6887/5157/files/25575429916.pdf
    • https://cdn.shopify.com/s/files/1/0429/4941/0979/files/aace_osteoporosis_guidelines_2016_ppt.pdf
    • https://cdn.shopify.com/s/files/1/0430/3929/3589/files/81173014592.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/73649427877.pdf
    • https://cdn.shopify.com/s/files/1/0437/3708/8154/files/4585423190.pdf
    • https://cdn.shopify.com/s/files/1/0429/3427/2159/files/36912592283.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/35535883354.pdf
    • https://cdn.shopify.com/s/files/1/0430/2084/5210/files/ropoporamifaj.pdf
    • https://cdn.shopify.com/s/files/1/0430/6305/0394/files/alginate_structure.pdf
    • https://cdn.shopify.com/s/files/1/0431/3251/8549/files/dafesuruzusulitijasa.pdf
    • https://cdn.shopify.com/s/files/1/0435/4218/4095/files/luwusutomogep.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/metegemekipezafekude.pdf
    • https://cdn.shopify.com/s/files/1/0441/4029/8392/files/netal.pdf
    • https://cdn.shopify.com/s/files/1/0432/4294/6728/files/ahmadu_bello_university_post_graduate_form.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000054f8.bin
bd5eb7a17195ddfa6d61f3b6ef8087c8a89c3672b1eb05de509dbf4ef750b3c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x54F8 5412 bytes
font_01_sfnt_off0000676d.bin
055858f5a25a2d170ac0a0c8d9b192f31bf56437270a8487e7964ace790899ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x676D 9816 bytes